Applicants own Swedish patent SE-0300784-6 (publication number 526 366) discloses and claims through connections (also referred to as vias) made in a wafer material from the native wafer itself. The vias thereby comprises the same material as the remainder of the wafer and will thus be capable of being processed in a more versatile manner, as describe in detail in said patent, the disclosure of which is incorporated herein in its entirety by reference.
However, for certain applications the resistivity that is attainable in these prior art vias may be to low, and it would be desirable to provide vias with very low resistivity.
It is known to provide vias made of metal, but the conventional methods used (sputtering, plating, or evaporation methods) are all suffering from the problem that it is difficult to fill very small holes with them. Metal vias only allows via last processes (e.g. CMOS structures must be made before via formation).